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C Henschke

Publications and source records attributed to C Henschke.

18 recordsLinked to original sources
PubMed2002

Consensus statements from the Second International Lung Cancer Molecular Biomarkers Workshop: a European strategy for developing lung cancer molecular diagnostics in high risk populations.

The Second Molecular Biomarkers Workshop was held at the Roy Castle International Centre for Lung Cancer Research in Liverpool, in June 2001 and it brought together experts in the clinical, epidemiological and molecular-pathology of lung cancer from Europe and the USA, to address issues surrounding the development of a European strategy for early lung cancer detection. The 2001 Workshop Breakout Groups concentrated on the current challenges in the early detection of lung cancer which need to be addressed in the light of the recent surge in interest in many countries for mounting new clinical trials to evaluate the utility of Spiral CT in early lung cancer detection. If population-based trials of CT screening are mounted it will also be a favorable clinical environment in which to evaluate efficiently recent advances in molecular screening and genotyping. The Workshop focused specifically on: a) clinical and molecular biomarkers, b) sputum as an early detection and diagnostic tool, c) validation of molecular markers prior to their use in early detection trials and d) ethical issues that have to be considered in early lung cancer detection trials. A distillation of the Workshop discussions is given in this article.

Biomarkers, Tumor↗
PubMed2001

Modeling of long-term screening for lung carcinoma.

BACKGROUND: Results from the Mayo Lung Project (MLP), a randomized clinical trial for the early detection of lung carcinoma, were interpreted as proof that the early detection of lung carcinoma by chest X-ray does not reduce the mortality from this disease. Recent analysis of extended follow-up data from the MLP subjects found that after approximately 20 years there still was no apparent difference in lung carcinoma mortality between a study group and a control group. METHODS: To view this result within context, the authors utilized a previously published simulation model of the MLP, with parametric values that were estimated at the time of the original publication based on the data collected by the MLP. RESULTS: The model produced predictions of the extended follow-up statistics that were found to be consistent with the data published in the prior study. The authors believe this provides long-term validation for the model. Conversely, the same model demonstrated that had the study subjects been screened annually for the extended follow-up period, the difference in mortality would be noticeable, even with the low sensitivity of chest X-ray detection. CONCLUSIONS: The results of current study strongly suggest that long-term screening with chest X-ray results in a reduction in lung carcinoma mortality. The limited extent of this benefit is the result of the low sensitivity of chest X-ray as a screening tool.

Follow-Up Studies↗
PubMed2001

[Screening for lung cancer--new possibilities with new methods!].

Screening for lung cancer has been regarded as unwarranted for many years. With new techniques, this is no longer the case. Screening with low dose CT scanning has been used in Japan and New York, among many places, for a number of years. We here describe some results. New lung cancers were found in 0.6 per cent of all participants in both studies at the yearly repeat scan. The tumors have been very small, almost all in Stage I, and survival is very good. Thus, the results are promising, and trials in Sweden will hopefully begin before long.

Controlled Clinical Trials as Topic↗
PubMed2000

Evaluation of clinical parameters to predict Mycobacterium tuberculosis in inpatients.

BACKGROUND: Respiratory isolation has been recommended for all patients with suspected tuberculosis (TB) to avoid transmission to other patients and health care personnel. In implementing these guidelines, patients with and without TB are frequently isolated, significantly increasing hospital costs. The objective of this study was to derive a clinical rule to predict the need for respiratory isolation of patients with suspected TB. METHODS: To identify potential predictors of the need for isolation, 56 inpatients with sputum cultures positive for TB were retrospectively compared with 56 controls who were isolated on admission to the hospital based on clinically suspected TB but whose sputum cultures tested negative for TB. Variables analyzed included TB risk factors, clinical symptoms, and findings from physical examination and chest radiography. RESULTS: Multivariate analysis revealed that the following factors were significantly associated with a culture positive for TB: presence of TB risk factors or symptoms (odds ratio [OR], 7.9 [95% confidence interval (CI), 4.4-24.2]), a positive purified protein derivative tuberculin test result (OR, 13.2 [95% CI, 4.4-40.7]), high temperature (OR, 2.8 [95% CI, 1.1-8.3]), and upper-lobe disease on chest radiograph (OR, 14.6 [95% CI, 3.7-57.5]). Shortness of breath (OR, 0.2 [95% CI, 0.12-0.53]) and crackles noted during the physical examination (OR, 0.29 [95% CI, 0.15-0.57]) were negative predictors of TB. A scoring system was developed using these variables. A patient's total score of 1 or higher indicated the need for respiratory isolation, accurately predicting a culture positive for TB (98% sensitivity [95% CI, 95%-100%]; 46% specificity [95% CI, 33%-59%]). CONCLUSION: Among inpatients with suspected active pulmonary TB, a prediction rule based on clinical and chest radiographic findings accurately identified patients requiring respiratory isolation.

Adult↗
PubMed1999

Two-dimensional multi-criterion segmentation of pulmonary nodules on helical CT images.

A multi-criterion algorithm for automatic delineation of small pulmonary nodules on helical CT images has been developed. In a slice-by-slice manner, the algorithm uses density, gradient strength, and a shape constraint of the nodule to automatically control segmentation process. The multiple criteria applied to separation of the nodule from its surrounding structures in lung are based on the fact that typical small pulmonary nodules on CT images have high densities, show a distinct difference in density at the boundary, and tend to be compact in shape. Prior to the segmentation, a region-of-interest containing the nodule is manually selected on the CT images. Then the segmentation process begins with a high density threshold that is decreased stepwise, resulting in expansion of the area of nodule candidates. This progressive region growing approach is terminated when subsequent thresholds provide either a diminished gradient strength of the nodule contour or significant changes of nodule shape from the compact form. The shape criterion added to the algorithm can effectively prevent the high density surrounding structures (e.g., blood vessels) from being falsely segmented as nodule, which occurs frequently when only the gradient strength criterion is applied. This has been demonstrated by examples given in the Results section. The algorithm's accuracy has been compared with that of radiologist's manual segmentation, and no statistically significant difference has been found between the nodule areas delineated by radiologist and those obtained by the multi-criterion algorithm. The improved nodule boundary allows for more accurate assessment of nodule size and hence nodule growth over a short time period, and for better characterization of nodule edges. This information is useful in determining malignancy status of a nodule at an early stage and thus provides significant guidance for further clinical management.

Algorithms↗
PubMed1995

Direct comparison of Sn-mesoporphyrin, an inhibitor of bilirubin production, and phototherapy in controlling hyperbilirubinemia in term and near-term newborns.

BACKGROUND: Sn-mesoporphyrin (SnMP) is a potent inhibitor of bilirubin production. In our previous studies a single dose (6 mumol/kg birth weight) significantly moderated hyperbilirubinemia and reduced phototherapy (PT) time by > 75% when administered within 24 hours of birth to preterm infants. OBJECTIVE: To directly compare the efficacy of SnMP and PT for controlling hyperbilirubinemia in term and near-term infants. METHODS: Two randomized, sequentially analyzed trials (Study I: male term infants; Study II: infants of both sexes and gestational age [GA] 245-265 days) were conducted. SnMP (6 mumol/kg birth weight) or PT (Phillips F20T12/BB lamps) was administered to paired infants according to strict criteria of plasma bilirubin levels and age. Time of enrollment and closure of cases and crossover, if necessary, of SnMP infants to PT or all infants to exchange transfusion were precisely defined in each pair. SnMP or PT was considered superior if the time between enrollment and closure of the case was reduced by > 24 hours over the alternative treatment or if crossover had occurred. RESULTS: None of the 44 SnMP-treated infants required supplemental PT. Of the 22 pairs of term infants enrolled in Study I, SnMP proved superior to PT in 20 and equal in two. Of the 20 pairs of near-term infants enrolled in Study II, SnMP was superior in 12 and PT in two; six were tied. Two SnMP-treated infants were unpaired. The PT-treated infants in Study I required an average of 33 hours of treatment; those in Study II, 48 hours. None of the enrolled infants required exchange transfusion or interruption of breast-feeding. In both studies, times between case enrollment and closure were reduced by > 30 hours in SnMP compared with PT infants; requirements for additional days of medical observation and bilirubin measurements were also significantly less in SnMP infants. CONCLUSION: A single dose of SnMP entirely supplanted the need for PT in jaundiced term and near-term newborns and significantly reduced medical resource use to monitor hyperbilirubinemia.

Female↗
PubMed1994

Diagnosis of pulmonary embolism at a large teaching hospital.

Pulmonary embolism (PE) is a common clinical entity, although the signs and symptoms that accompany it are nonspecific. This has led to the development of several diagnostic algorithms for diagnosis of PE. These approaches combine noninvasive tests such as ventilation/perfusion (V/Q) lung scanning, impedance plethysmography, and ultrasound, with invasive techniques such as venography and pulmonary angiography. To investigate the manner in which clinicians select and use these various diagnostic strategies, we retrospectively reviewed 316 consecutive cases of suspected PE to determine the sequence and type of diagnostic strategy employed by clinicians. We found that in the majority of cases, physicians chose not to further pursue a diagnosis of PE if the V/Q scan was nondiagnostic. These results suggest that physician behavior is often at variance with published clinical recommendations and that the implementation of clinical practice guidelines needs to be further examined.

Angiography↗
PubMed1994

Radiographic features useful for establishing patient identity from improperly labeled portable chest radiographs.

Radiologists in hospital practice often encounter radiographs that either bear no patient identification or are incorrectly labeled as those of a different patient. To avoid repeating these improperly labeled radiographs, and to establish correct patient identity, most radiologists compare these radiographs with previous radiographs of several patients. This happens most often with portable chest radiographs. To study the reliability of various surgical, pathologic, and anatomic features and to help establish a fast and accurate method of establishing the correct patient identity, we performed a retrospective study of 50 patients in the intensive care unit. The characteristic location and configuration of surgical material, fractures, and dense parenchymal/pleural scars with or without calcifications are extremely helpful in establishing patient identity. In the vast majority of patients who lack such characteristic surgical and pathologic features, the anatomic structures that are most reliable for identification purposes are, in order of decreasing reliability, the transverse processes of the first thoracic vertebrae and the adjoining tubercles of the first ribs, the spinous processes, and the scapular wings. We believe that this information will help radiologists to identify the right patient when radiographs are incorrectly labeled.

Adult↗
PubMed1994

Control of jaundice in preterm newborns by an inhibitor of bilirubin production: studies with tin-mesoporphyrin.

BACKGROUND: Studies in vitro, in animal models, and in adult and newborn humans have demonstrated that certain tin(Sn)-porphyrins that competitively inhibit the activity of heme oxygenase, the rate-limiting enzyme in heme catabolism, reduce production of bilirubin and can thereby substantially diminish plasma levels of the bile pigment. OBJECTIVES: To assess the effectiveness of increasing doses of the heme oxygenase inhibitor, Sn-mesoporphyrin (SnMP), in moderating the development of significant hyperbilirubinemia and thus the requirements for phototherapy in preterm newborns. METHODS: In five randomized, blinded, placebo-controlled trials, SnMP in increasing doses from 1 mumol to 6 mumol/kg body weight was administered intramuscularly in the first 24 hours of life in preterm newborns of 210 to 251 days gestational age. "Special blue" lamps (Phillips F20T12/BB) were used for phototherapy in newborns exceeding a predetermined plasma bilirubin concentration, irrespective of study group. RESULTS: A total of 517 newborns were randomized in the five trials carried out sequentially over a 4-year period. SnMP in a dose-related manner significantly ameliorated the course of hyperbilirubinemia in the treated newborns of all gestational ages. With a SnMP dose of 6 mumol/kg body weight, the mean peak incremental plasma bilirubin concentration was reduced by 41% and the phototherapy requirements were decreased by 76% compared to control subjects. Erythema observed in a few SnMP-treated newborns who required phototherapy was mild, transient, and without sequelae. No other untoward effects were observed during hospitalization or at a follow-up at post-term age of 3 and 18 months. CONCLUSIONS: SnMP, by inhibiting the production of bilirubin, substantially moderates the development of hyperbilirubinemia in preterm newborns. This compound and similarly acting enzyme inhibitors merit further clinical study as agents for controlling neonatal hyperbilirubinemia, particularly in neonatal populations for whom other treatment modalities are not available.

Bilirubin↗
PubMed1989

Computed tomography versus magnetic resonance imaging of the brain. A collaborative interinstitutional study.

A retrospective study (1983-1984) of magnetic resonance imaging (MRI) and computed tomography (CT) examinations in 471 patients with known pathology in the brain and craniocervical junction was conducted in order to determine the relative efficacy of MRI versus CT. All MRI examinations involved slice thickness greater than 10 mm, and only single-slice single-echo or multislice single-echo imaging techniques were available. These studies were evaluated independently by two neuroradiologists from a panel of six for anatomic abnormalities, lesion contrast, and radiologist's impression. Results, which excluded microadenomas of the pituitary and approximately 9% of studies in which consensus was not achieved by the readers, were as follows: (1) 14% of the studies were positive on MRI but normal on CT; (2) in 55% of the studies, MRI was better than CT; (3) MRI was equal or better than CT in 95% of the studies; and (4) CT was better than MRI in 5% (21/421) of the examinations. There were no patients in this series where CT was positive but MRI missed the abnormality.

Adult↗
PubMed1983

Quantitative analysis of left ventricular wall motion and thickness using two-dimensional echocardiography.

The real time two-dimensional ultrasonic imaging of the left ventricle made possible segmental echocardiographic measurements of wall motion and thickening and thinning. The underlying hypothesis is that measurements of regional wall motion could quantify the extent of myocardial ischemia and infarction; the method could be used as a truly non-invasive tool to assess the severity of damage from infarction and the effects of interventions designed to limit infarcts. The method is operator interactive. Each patient's data could be compared with data for a normal group. The selection criteria for the normal patients have been described. The confidence region of the normal group and the effect of averaging over three tracings for three heartbeats have been computed. Technical difficulties inherent in the method and possible improvements are discussed.

Computers↗
PubMed1982

Pathophysiology of chest pain in patients with cardiomyopathies and normal coronary arteries.

To clarify the pathogenesis of chest pain in patients with cardiomyopathies, we compared coronary blood flow and other indicators of ischemia at rest and during pacing-induced tachycardia in nine patients with cardiomyopathy (four hypertrophic and five congestive) and in five control subjects. Coronary blood flow was reduced at rest and during pacing in cardiomyopathy patients compared with controls. In patients with hypertrophic cardiomyopathy, pacing induced chest pain in all, increased ST-segment depression in three patients and increased coronary venous lactate concentration. With pacing, two of five patients with congestive cardiomyopathy had chest discomfort and three had increased ST-segment depression, but coronary venous lactate concentration did not change significantly. In both groups of cardiomyopathies, the ratio of the systolic and diastolic pressure-time indexes tended to decrease more than in controls during pacing. Thus, myocardial perfusion is decreased in patients with cardiomyopathy, both at rest and during pacing. The changes detected during pacing point to subendocardial ischemia as the likely mechanism for angina in hypertrophic and possibly also in congestive cardiomyopathy.

Angina Pectoris↗
PubMed1981

Tricuspid stenosis masquerading as right ventricular failure in a patient with a prosthetic mitral valve.

Echocardiographic, phonocardiographic, and pulse tracing recordings demonstrated clinically unsuspected tricuspid stenosis in a 53-year-old man with a prosthetic mitral valve and signs of right heart failure. Physiologic correlates of the patient's heart sounds and diastolic murmur were studied by simultaneous M-mode echocardiograms and phonocardiograms. Cardiac catheterization and subsequent valve surgery confirmed the presence of tricuspid stenosis. It is important to consider the diagnosis of tricuspid stenosis in all patients with a history of rheumatic mitral valve disease who develop findings suggestive of right ventricular failure.

Cardiac Catheterization↗
PubMed1981

Prediction of postoperative performance in aortic valve disease.

A new direct method has been developed for predicting postoperative performance in patients undergoing aortic valve replacement. Employing micromanometry and cineangiography, a number of conventional hemodynamic and angiographic variables, including the peak value of the first derivative of ventricular pressure divided by ventricular pressure (dP/dt/P)max, were evaluated in 171 patients studied preoperatively and in 44 patients studied pre- and postoperatively with an additional 14 patients serving as control subjects. Normal contractile state relations (dP/dt/P)max versus end-diastolic pressure (over a range of 125 mm Hg or less to more than 15 mm Hg) were derived from patients whose preoperative ejection fraction and peak wall stress were equal to or more than control mean--2 standard deviations. Postoperative function was predicted to be abnormal (ejection fraction less than control mean--2 standard deviations) if preoperative values of (dP/dt/P)max and end-diastolic pressure fell below the 95 percent confidence bands of these contractile state relations. The method accurately predicted postoperative function in 40 of 44 patients with a sensitivity of 100 percent. This result was confirmed by a discriminant function analysis (based on preoperative ejection fraction, end-diastolic pressure and [dP/dt/P]max) that yielded correct classifications in 42 of 44 patients. These studies indicate that the preoperative contractile state of the myocardium is the major determinant of postoperative performance in aortic valve disease.

Aortic Valve↗